The zero insertion force electric connector of a central processing unit is formed by a base, a driving rod and a movable plate. The top of the slot is formed with a power supply inserting holes for being inserted by terminals and matched with the pins of the central processing unit. The driving rod is formed at the rear side of the top of the base and it is covered and positioned by the movable plate. By upward and downward movement of the driving rod, the movable plate may move forwards and backwards. The slots on the surface of the movable plate are correspondent to the inserting holes on the surface of the base. If the driving rod is moved upwards, the slots on the movable plate are alternatively arranged with the inserting holes on the base. If the driving rod is moved downwards, they are aligned. Therefore, the plurality of pins of the central processing unit are inserted into the slots on the surface of the movable plate, respectively. When the slot is moved downwards and is resisted to be positioned, the movable plate will move to a predetermined position so that the pins of the central processing unit are clamped in the terminals within the slots. On the contrary, the pins of the central processing unit will separate from the terminals in the slots.
The prior art terminal has only one inclined protruded elastic contact with a small contact area with the pins of the central processing unit. A single point contact structure is formed. Thus, it is not suitable to be used in current high frequency central processing unit.
In general, as a prior art terminal is inserted into a slot of a base, a gap is formed therebetween so that the terminal is easy to vibrate. Therefore, as the leg post of the terminal is welded in a circuit board, the welding agent is easy to flow into the gap. This has a bad effect to the quality of a zero insertion force electric connector. Therefore, the present invention provides a zero insertion force electric connector, in which two clamping pieces are formed as a cambered structure with three cambered portions. The apexes of cambered portions are installed with a three-fulcrum structure of an upper fulcrum, a middle fulcrum and a lower fulcrum so as to be steadily and effective supported in the slots of the base. Moreover, by two pits on the bottom of the slot, the welding agent is prevented from flowing into the gap between the terminal and slot.